Patent Application
20250153472
Aspects hereof relate to polymer-based construction materials comprising combining a thermoplastic polymer and a thermoset polymer, wherein the thermoset polymer is a cross-linked high density polyethylene.
Man-made alternatives to naturally occurring materials such as wood can provide a number of advantages in construction and consumer products. For example, wood can rot, warp, splinter, discolor or bleach; while polymer-based materials, such as materials that have an outer layer made of high-density polyethylene (HDPE), may be dent and impact resistant, resist rotting, include UV resistant additives, be sealed to prevent discoloration, and so on. The combination of wood fibers and plastic (e.g., HDPE, low-density polyethylene (LDPE), etc.) gives composite decking some of the aesthetics of wood while benefiting from the durability and low maintenance of plastic.
Although traditional polymer-based decking materials offer several advantages, they do come with certain disadvantages. For example, even though polymer-based decking is designed to resist scratching better than uncapped composites, it is still susceptible to marring or dents from furniture, pet claws, and other sharp objects. Another disadvantage with traditional polymer-based decking is low slip resistance when the surface of the polymer-based material is wet.
Attempts have been made to manufacture polymer-based construction materials with enhanced slip resistance and scratch resistance to address consumer concerns and improve the longevity and safety of traditional HDPE capped decking materials. For example, several manufacturers have incorporated textured surfaces into their products, mimicking the grain of real wood to help with slip resistance when wet. However, textured surfaces can be challenging to clean. Additionally, high traffic or heavy use can cause uneven wear over time, which diminishes the intended functional benefits of the texture. Textured surfaces also present a challenge when it comes to achieving a consistent look across the surface. For example, maintaining consistency of textured surfaces can be difficult when, or if, the surface were to need repairs.
Other attempts to increase scratch resistance include incorporation of reinforcing additives, such as adding some mineral compositions to the composite mix to enhance the overall durability and scratch resistance. Increasing inorganic mineral content can improve scratch resistance. However, excessive amounts may lead to unintended consequences, such as scratch whitening, where scratches appear more visibly white against the material's surface. Further, traditional reinforcing materials, particularly certain fibers or minerals, can increase the weight of the composite, which may not be desirable for lightweight applications. Incorporating these fibers and minerals may complicate the manufacturing process, requiring specialized equipment, additional processing steps, and more rigorous quality control. Additionally, some inorganic mineral reinforcements tend to absorb or interact with pigments differently than the polymer matrix (e.g., HDPE), resulting in inconsistencies in color distribution. This differential pigment interaction may further highlight any scratches that do form, reducing the material's overall aesthetic appeal.
Accordingly, aspects described herein provide for polymer-based building materials including a thermoplastic polymer and a thermoset polymer as well as systems and methods for producing the same.
The present invention is described in detail herein with reference to the attached drawing figures, wherein:
As mentioned above, using polymer-based construction materials can provide a number of advantages in construction and consumer products compared to their naturally occurring counterparts. However, traditional HDPE capped decking materials are susceptible to marring or dents, and can be slippery when the surface is wet.
Some aspects described herein overcome these problems and provide polymer-based construction materials, systems, and methods for producing polymer-based construction materials that combine a thermoplastic polymer with a thermoset polymer. Embodiments described herein allow for the retention of key thermoplastic properties while incorporating thermoset characteristics to form the cap, distinguishing it from traditional cross-linking approaches.
Typically, cross-linking has involved treating the entire polymer matrix via secondary processes (such as electron beam irradiation or UV irradiation), or through comprehensive reactive extrusion using cross-linking agents, such as peroxide. These traditional methods generally involve stationary, secondary treatments that cross-link the outer surfaces of the polymer more intensely than the interior. In other words, cross-linking is most concentrated at the surface, with less cross-linking occurring toward the interior, due to limited penetration depth of UV or e-beam radiation, leading to inconsistent performance across the material. Moreover, these traditional processes present several challenges, including the need for additional equipment, complex quality control, and precise adjustment of treatment parameters to control cross-linking ratios and distribution, which can lead to reproducibility issues and increased production costs.
In contrast, the approach described herein integrates ground cross-linked polyethylene (PEX) directly into the thermoplastic HDPE matrix, creating a homogeneous, non-gradient distribution of cross-linked particles throughout the thickness of the cap. This uniform structure allows for consistent cross-linking proportions, ensuring that the cap retains key thermoplastic properties while incorporating thermoset characteristics in a balanced manner—achieving a harder, more durable surface without compromising the thermoplastic's inherent benefits. Moreover, this method eliminates the need for additional equipment, complex quality control, and precise treatment adjustments required by traditional cross-linking techniques, simplifying manufacturing and improving reproducibility. Additionally, it may allow for selective customization of the cross-linked content within the thermoplastic, providing a balance of properties from both polymer types.
For example, adding a thermoset polymer, such as cross-linked HDPE, into the traditional thermoplastic polymer HDPE may facilitate formation of a capped decking material having comparatively improved slip, scratch, marring, and heat resistance. Cross-linked HDPE is often referred to as PEX, and is a form of HDPE that has undergone a chemical or physical process to create covalent bonds (i.e., cross-links) between its polymer chains. The cross-linking results in a modified HDPE with improved properties compared to conventional HDPE, including thermal stability, chemical resistance, durability, creep resistance, and the like. Once the HDPE undergoes the cross-linking process, it effectively changes its nature from a thermoplastic polymer to a thermoset polymer.
In aspects, incorporating ground PEX into the thermoplastic matrix may produce a more uniform distribution of cross-linking throughout the material thickness compared to traditional methods. While the extrusion process may cause some particles to migrate slightly toward the surface, this gradient effect is minimal compared to the pronounced layering seen in traditional methods. The screw shear within the extrusion process further promotes even dispersion of PEX particles, ensuring consistent integration.
In aspects, cross-linked HDPE (i.e., PEX) is incorporated into traditional thermoplastic HDPE to produce a capped decking material with improved durability. This controlled integration may enable the retention of essential thermoplastic characteristics with additional benefits such as increased thermal stability, chemical resistance, flexibility, and creep resistance-without the need for secondary processes like UV or E-beam irradiation that often make materials difficult to reprocess. Additionally, residual peroxide within the PEX material may facilitate controlled cross-linking during processing, enhancing the material's properties. Thus, the PEX may act as a functional filler rather than a simple additive, contributing actively to the enhanced durability, scratch resistance, slip resistance, and heat resistance of the final product. Importantly, the thermoplastic matrix retains its recyclability and reprocessability, as the cross-linking is well-controlled and does not compromise the thermoplastic's core properties.
Accordingly, some aspects described herein are directed to a method of preparing a polymer-based building material. The method includes providing a first extruder with a first polymer-based mixture including a first amount of a thermoplastic polymer and a second amount of a thermoset polymer, where the first amount and second amount are different. The first polymer-based mixture is heated along a length of the first extruder and then extruded, wherein the first polymer-based mixture includes the thermoplastic polymer and the thermoset polymer.
Another aspect described herein is directed to a polymer-based building material. The polymer-based building material includes a core having a first thickness extending between a first planar surface and a second planar surface. The polymer-based building material also includes a cap that is adjacent at least the first planar surface and includes a thermoplastic polymer and a thermoset polymer.
Another aspect described herein is directed to a polymer-based building material. The polymer-based building material includes a core having a first planar surface and a second planar surface. The polymer-based building material also includes a cap that is adjacent to the first planar surface and includes a polymeric composition having a thermoplastic polymer and a thermoset polymer, wherein the thermoset polymer in the polymeric composition is in a range of up to 20% by weight.
Yet another aspect described herein is directed to a polymer-based building material. The polymer-based building material includes a first cap portion having a first thickness, wherein the first cap portion extends between a first planar surface and a second planar surface and includes a thermoset polymer and a thermoplastic polymer. The polymer-based building material also includes a core that is adjacent to at least the second planar surface, wherein the first cap portion at least partially covers an outer surface of the core.
With respect to
The polymer-based construction material 100 comprises a length 102, a width 106, and gauge (thickness) 108. The length 102 may be any length and may vary based on the intended use. For example, the length 102 is between 0.5 feet (ft.) and 60 ft. in some aspects. However, it is contemplated that length 102 can be any length.
The width 106 may be any value and may vary based on the intended use. For example, a polymer-based material intended for use as a siding component may be a first width, while a polymer-based construction material intended for use as a trim board may be a second width, while a polymer-based construction material intended for use as a construction accessory may be a third width, and so on. Additionally, in some aspects, a polymer-based construction material (such as construction material 100) can be cut into a selectable combination of uniform and/or non-uniform widths.
The gauge 108 may be any thickness and may vary based on the intended use. In some aspects, the gauge 108 is between 0.10 inches and 3.00 inches. In some aspects, the gauge 108 is between 0.125 inches and 2.00 inches. In some aspects, the gauge 108 is between 0.25 inches and 1.75 inches. In some aspects, the gauge 108 is between 0.5 inches and 1.25 inch. In an aspect, the gauge 108 is 0.25 inches.
Polymer-based construction material 100 also comprises a first primary surface 104 and a second primary surface 110. The primary surfaces 104, 110, or both are generally the surfaces intended for exposure or contact during normal use. For example, where the polymer-based construction material has an intended end use as a board in a deck, the primary surface of the polymer-based construction material would form part of the decking surface intended for contact with users of the deck.
Turning to
The polymer-based cap 202 comprises a first polymer-based mixture including a thermoplastic polymer and a thermoset polymer. The thermoset polymer may include cross-linked HDPE (i.e., PEX) in some aspects. The thermoplastic polymer of the polymer-based cap 202 may be in a range of up to 20% by weight of the first polymer-based mixture. For example, in an aspect, the thermoset polymer is 5% by weight of the first polymer-based mixture. In at least one aspect, the thermoplastic polymer of the first polymer-based mixture includes one or more HDPE, LDPE, or polypropylene (PP) and comprises at least 80% of a polymer-based mixture by weight. The thermoplastic polymer of the first polymer-based mixture may include one or more recycled polymers and/or virgin polymers in some aspects. As used herein, a virgin polymeric resin refers to a resin that includes at least one polymer that is not recycled or a recovered scrap. As used herein, a recycled polymer is a polymer that has been processed from post-consumer or post-industrial plastic waste. Instead of these plastics ending up in landfills or being incinerated, they are collected, processed, and then remanufactured into new plastic products. For example, the thermoplastic polymer may include recycled ultra-high molecular weight polyethylene (UHMWPE), recycled HDPE, recycled low density polyethylene (LDPE) or any combination thereof. Additionally, in at least one aspect, the polymer-based cap 202 does not comprise cellulose.
The polymer-based core 212 can comprise a second polymer-based mixture that is different from the first polymer-based mixture, and includes a second thermoplastic polymer. In some aspects the polymer-based core 212 can comprise a filler. The filler is a material added to the polymer to enhance certain properties, reduce product cost, incorporate recycled materials, or any combination thereof. Some examples of fillers include wood fibers or flour, mineral fillers, glass fibers, carbon black, and recycled materials. The exact formulation of the core mixture, including the type and proportion of the filler can vary. The core has a first thickness extending between the first planar surface 214 and the second planar surface 216. Alternatively, the polymer-based core 212 includes a first core portion (not shown) perpendicularly connecting the first planar surface 214 to the second planar surface 216. In some embodiments, the polymer-based cap 202 can be used as a single layer on building products and there may not be a different material used for the polymer-based core 212. In other words, the entire profile may be completely formed from the polymer mix that forms the polymer-based cap 202.
As depicted in
Continuing with reference
The width 210 of the multicomponent polymer-based construction materials 200, 230, 240, and 250 may be any width and may vary based on the intended use. For example, in some aspects, the width 210 is 3 inches (76.2 mm) or 152 inches (3860.8 mm). In some aspects, the width 210 is between 3 inches (76.2 mm) and 152 inches (3860.8 mm).
Turning to
With reference to
Accordingly, in some aspects of block 510 a first extruder is provided with a first polymer-based mixture, including a first amount of a thermoplastic polymer and a second amount of a thermoset polymer, wherein the second amount is different from the first amount. In aspects, the thermoplastic polymer comprises recycled polymeric material that ranges from 20%-50% by weight. In other aspects, the thermoset polymer comprises a range of 0.1% and 20% by weight. In aspects, the thermoset polymer comprises a range of 10% and 20% by weight. In example aspects, the thermoset polymer comprises 15% by weight. In alternative aspects, the thermoset polymer comprises 13% by weight. In alternative aspects, the thermoset polymer comprises 11% by weight. In alternative embodiments, the thermoset polymer comprises a range of 1% and 9% by weight. In aspects, the thermoset polymer comprises a range of 2% and 8% by weight. In aspects, the thermoset polymer comprises a range of 3% and 7% by weight. In aspects, the thermoset polymer comprises a range of 4% and 6% by weight. For example, in a particular aspect, the thermoset polymer is 5% by weight. At block 520, the first polymer-based mixture is heated along a length of the first extruder. And finally at block 530, the first polymer-based mixture is extruded from the first extruder, wherein the first polymer-based mixture includes a first component comprising the thermoplastic polymer and the thermoset polymer. Additionally, or alternatively, the method could further comprise a second extruder with a second polymer-based mixture including a second thermoplastic polymer and a filler. The second polymer-based mixture can be co-extruded with the first polymer-based mixture, wherein the first polymer-based mixture at least partially surrounds at least one surface of the second polymer-based mixture (such as discussed in reference to
The subject matter of the technology described herein is described with specificity to meet statutory requirements. However, the description itself is not intended to limit the scope of this patent. Rather, the inventors have contemplated that the claimed subject matter might also be embodied in other ways, to include different steps or combinations of steps similar to the ones described in this document, in conjunction with other present or future technologies. Moreover, although the terms “step” and/or “block” may be used herein to connote different elements of the methods employed, the terms should not be interpreted as implying any particular order among or between various steps herein disclosed unless and except when the order of individual steps is explicitly described.
As used herein and in connection with the claims listed hereinafter, the terminology “any of clauses” or similar variations of said terminology is intended to be interpreted such that features of claims/clauses may be combined in any combination. For example, an exemplary clause 4 may indicate the method/apparatus of any of clauses 1 through 3, which is intended to be interpreted such that features of clause 1 and clause 4 may be combined, elements of clause 2 and clause 4 may be combined, elements of clause 3 and 4 may be combined, elements of clauses 1, 2, and 4 may be combined, elements of clauses 2, 3, and 4 may be combined, elements of clauses 1, 2, 3, and 4 may be combined, and/or other variations. Further, the terminology “any of clauses” or similar variations of said terminology is intended to include “any one of clauses” or other variations of such terminology, as indicated by some of the examples provided above.
Clause 1. A method of preparing a polymer-based building material, the method comprising: providing a first extruder with a first polymer-based mixture including a first amount of a thermoplastic polymer and a second amount of a thermoset polymer; heating the first polymer-based mixture along a length of the first extruder; and extruding the first polymer-based mixture from the first extruder, wherein the first polymer-based mixture includes a first component comprising the thermoplastic polymer and the thermoset polymer.
Clause 2. The method of clause 1, wherein the thermoset polymer comprises recycled polymeric material that ranges from 20%-50% by weight
Clause 3. The method of clause 1 or 2, wherein the thermoplastic polymer comprises one or more of recycled high density polyethylene (HDPE), recycled low density polyethylene (LDPE), or polypropylene (PP).
Clause 4. The method of any of clauses 1 through 3, wherein the thermoset polymer comprises a cross-linked high density polyethylene.
Clause 5. The method of any of clauses 1 through 4, wherein the thermoplastic polymer comprises at least 80% of the first polymer-based mixture by weight.
Clause 6. The method of any of clauses 1 through 5, wherein the thermoset polymer comprises a range of 0.1% and 20% by weight.
Clause 7. The method of any of clauses 1 through 6, wherein the thermoset polymer is 5% by weight.
Clause 8. The method of clauses 1 through 7, further comprising: providing a second extruder with a second polymer-based mixture including a second thermoplastic polymer and a filler; and co-extruding the second polymer-based mixture with the first polymer-based mixture, wherein the first polymer-based mixture at least partially surrounds at least one surface of the second polymer-based mixture
Clause 9. A polymer-based building material comprising: a first cap portion having a first thickness, wherein the first cap portion extends between a first planar surface and a second planar surface and includes a thermoplastic polymer and a thermoset polymer; and a core, the core adjacent at least the second planar surface, wherein the first cap portion at least partially covers an outer surface the core.
Clause 10. The building material of clause 9, further comprising a second cap portion having a second thickness that extends between a third planar surface and a fourth planar surface, and includes a thermoplastic polymer and a thermoset polymer.
Clause 11. The building material of clause 9 or 10, wherein the second cap portion is affixed to an outer surface of the core opposite the first cap portion, wherein the second cap portion at least partially covers the outer surface of the core on the third planar surface.
Clause 12. The building material of any of clauses 9 through 11, wherein the core has a first thickness extending between the second planar surface and the third planar surface.
Clause 13. The building material of any of clauses 9 through 12, wherein the thermoset polymer is a cross-linked high density polyethylene (HDPE).
Clause 14. The building material of any of clauses 9 through 13, wherein the thermoplastic polymer comprises one or more of recycled high density polyethylene (HDPE) or polypropylene (PP).
Clause 15. The building material of any of clauses 9 through 13, wherein the thermoplastic polymer comprises a virgin polymer.
Clause 16. The building material of any of clauses 9 through 15, wherein the cap does not comprise cellulose.
Clause 17. The building material of any of clauses 9 through 16, wherein the core includes a first core portion perpendicularly connecting the first planar surface to the second planar surface.
Clause 18. The building material of any of clauses 9 through 17, wherein the first cap portion includes a subsection that is adjacent to at least a portion of the first core portion.
Clause 19. The building material of any of clauses 9 through 18, wherein the first cap portion has a first thickness and the second cap portion has a second thickness.
Clause 20. The building material of any of clauses 9 through 19, wherein the first cap portion and the second cap portion are connected by a joining cap member that is perpendicular to the first cap portion and the second cap portion and surrounds at least a portion of the core.
Clause 21. The building material of any of clauses 9 through 20, wherein the thermoset polymer comprises a range of 0.1% and 20% by weight.
Clause 22. A polymer-based building material, comprising: a core having a first planar surface and a second planar surface; and a cap adjacent to the first planar surface, the cap including a polymeric composition having a thermoplastic polymer and a thermoset polymer, wherein the thermoset polymer in the polymeric composition is in a range of up to 20% by weight.
Clause 23. The building material of clause 22, wherein the thermoset polymer is a cross-linked high density polyethylene (HDPE).
Clause 24. The building material of any of clauses 22 through 23, wherein the thermoplastic polymer comprises one or more of recycled high density polyethylene (HDPE), polypropylene (PP), or a virgin polymer.
Clause 25. The building material of any of clauses 22 through 24, wherein the thermoplastic polymer comprises at least 80% of a polymer-based mixture by weight.
Clause 26. The building material of any of clauses 22 through 25, wherein the thermoset polymer is 5% by weight.
Clause 27. The building material of any of clauses 22 through 26, wherein the cap does not comprise cellulose.
Clause 28. The building material of any of clauses 22 through 27, wherein the core includes a first core portion perpendicularly connecting the first planar surface to the second planar surface.
Clause 29. The building material of any of clauses 22 through 28, wherein the cap further comprises: a first cap portion having a subsection that is adjacent to at least a portion of the first core portion; and a second cap portion, wherein the first cap portion has a first thickness and the second cap portion has a second thickness.
Clause 30. The building material of any of clauses 22 through 29, wherein the first cap portion and the second cap portion are connected by a third cap portion that is perpendicular to the first cap portion and the second cap portion and surrounds at least a portion of the core.
This application having entitled “Polymer-Based Construction Materials” claims the benefit of priority of U.S. App. No. 63/598,519, filed Nov. 13, 2023, and entitled “Polymer-Based Construction Materials.” The entirety of the aforementioned application is incorporated by reference herein.
| Number | Date | Country | |
|---|---|---|---|
| 63598519 | Nov 2023 | US |
